Superplasticity and diffusion bonding of magnesium alloy ZK60

Superplasticity of as-rolled ZK60 magnesium alloy sheets, with the average grain size of 8.2 mu m, was investigated at a strain rate of 5.56 X 10(-4) - 5.56 X 10(-2) s(-1) at 573 - 673 K. The microstructure evolution during the superplastic deformation shows that the alloy deforms in a superplastic manner at the temperature from 573 K to 673 K. Diffusion bonding tests were carried out on the Gleeble1500 testing machine and the specimens were successfully diffusion bonded at the superplastic temperature. The maximum specific strength is 0.82 at a bonding pressure of 10 MPa for holding time 1 h at 673 K. The microstructures of the joints were observed through OM and SEM. There is no bond line visible in the original interfaces of sound joint with high specific strength.